...with the pressure loss. We then installed the 2.8-inch pulley, increasing boost to 10 psi and also increased timing to 27 degrees. Our first pull went smoothly, and before even looking at the dyno graphs, we backed it with another pull with a little more temperature in the engine. The results were outstanding. We made max torque of 581 lb-ft, and max horsepower of 555, an increase of 138 lb-ft of torque and 87 hp.